Inks used in ink jet printing systems typically are comprised of various dyes either dissolved in water or an organic solvent or mixtures thereof. There is a need for inks having higher quality images, printing speed, improved water-fastness and lightfastness.
U.S. Pat. No. 5,198,022 describes certain alkali-soluble azo dyes for waterfast ink it compositions.
U.S. Pat. No. 5,667,571 describes certain non-pollutive ink compositions using alcohol or glycol ether as solvent, which can be used as writing ink, (industrial) ink jet printing ink, stamp ink, etc. Certain triazinylamino substituted disazo dyes are described.
U.S. Pat. No. 5,795,970 describes certain disazo dyes usefulI in ink compositions which claims to provide sharp printing images having high optical density and no bleeding which also result in rapid fixing of the ink, water resistance and light resistance, even when printed on plain paper.
U.S. Pat. No. 5,753,016 describes certain disazo dyes which are useful in ink compositions and claim to offer a combination of a high-quality image with a waterfast printing image.
U.S. Pat. No. 5,453,495 describes certain piperazinyl substituted disazo dyes which are useful in ink jet compositions.
U.S. Pat. No. 5,891,230 describes certain disazo dyes usefull in ink jet printing. Further examples of disazo dyes can be found in the following: U.S. Pat. Nos. 5,725,644; 5,480,478; 5,888,286; 5,882,392; 5,843,218; and 5,756,693.